The MAX1744/MAX1745 are step-down DC-DC controllers capable of handling up to 36V inputs. These parts use a proprietary current-limited control scheme for excellent light- and full-load efficiency, while their 330kHz (max) switching frequency permits small external components for space-critical applications. Operation to 100% duty cycle permits the lowest possible dropout voltage. The MAX1744 contains an internal feedback network that provides a pin-selectable output voltage of either 3.3V or 5V. The MAX1745 uses an external feedback network to generate an adjustable output voltage between 1.25V and 18V.